Drying apparatus



June 6, 1967 E. MAXWELL DRYING APPARATUS 5 Sheets-Sheet 1 Filed March25, 1965 ATTORNEY E. MAXWELL DRYING APPARATUS June 6, 1967 Filed March25, 1965 5 Sheets-Sheet, 2

June 6, 1967 M L DRYING APPARATUS 5 Shets-Sheet 3 Filed March ,25, 1965ATTORNEY J 6, 19 7 E. MAXWELL DRYING APPARATUS 5 Sheets-Sheet 4 FiledMarch 25, 1965 tllllll rml l INVENTOR Ear/ :0 A1 ax :11

E. MAXWELL DRYING APPARATUS Jun 6, 1967 Filed March 25, 1965 5Sheets-Sheet 5 INVENTOR Etufdzna m 4. w Ff United States Patent Office3,323,228 Patented June 6, 1967 3,323,228 DRYING APPARATUS EustaceMaxwell, 37 Buckingham Terrace, Edinburgh, Scotland Filed Mar. 25, 1965,Ser. No. 442,675 Claims priori application Great Britain, Apr. 2, 1964,13,576/64; Feb. 3, 1965, 4,616/65 6 Claims. (Cl. 34-229) This inventionrelates to an improved form of drying apparatus of the kind in which astream of air is employed to remove water droplets from a non-absorbentsurface. Specifically this invention relates to apparatus for drying theexternal surface of a vehicle after it has been washed.

Vehicle drying apparatus has been proposed in which means is providedfor directing high velocity air streams into a vehicle-receiving dryingspace of substantially constant size and shape. In this type ofapparatus the drying space must be high enough to receive the tallestvehicle and wide enough to receive the widest Vehicle which it isanticipated will be dried with the apparatus. Since normally, a range ofdifferent sizes of vehicles is processed through a car-washing plant,this means, in practice, that to achieve optimum drying of smallvehicles more powerful means must be provided on the apparatus forgenerating the air streams than would be required if the apparatus wereto be used solely for drying the largest vehicles for which it wasdesigned.

This invention relates to drying apparatus in which the dimensions ofthe vehicle-receiving drying space are automatically adjusted inrelation to the size of the vehicle being dried.

According to the invention vehicle drying apparatus comprises at leastone unit having an air duct terminating in an outlet nozzle, means forexpelling air through the nozzle, sensingmeans disposed, in thedirection of air flow through the nozzle, forwardly of the nozzle andadapted to sense the proximity of the external surface of a vehicle tothe nozzle during relative movement of the vehicle past the nozzle andmeans operatively coupled to the sensing means for controlling themovement of the nozzle so that the nozzle closely follows the contoursof the external surface of the vehicle during at least a part of saidrelative movement.

In a preferred form of drying apparatus in accordance with theinvention, three units are employed, one positioned above the vehicle(hereinafter referred to as the top unit) and one positioned on eachside of the vehicle (each hereinafter referred to as a side unit). Theoutlet nozzle of each unit is conveniently slit-shaped, with the narrowdimension substantially at right angles to the direction of saidrelative movement of the vehicle past the nozzle, the nozzle of the topunit being substantially horizontal and the nozzle of each side unitbeing substantially vertical.

The means for expelling air through the nozzle of each unit ispreferably an electrically powered fan or blower mounted in the air ductwith the duct tapering towards the outlet nozzle.

The sensing means of each unit may embody one or more resilient rollersextending the entire Width of the duct at the outlet nozzle.Alternatively, resilient rollers may be used in combination with aphoto-electric sensing means.

Two specific forms of vehicles drying apparatus in accordance with theinvention will now be described, by way of example, with reference tothe accompanying drawings, in which:

FIGURE 1 is a perspective view of the top unit of a first form ofapparatus, 1

FIGURE 2 is a perspective view of the side unit of the first form ofapparatus,

FIGURE 3 is a diagrammatic illustration of the manner in which the airduct of the side unit of FIGURE 2 moves in response to the passage of avehicle therepast.

FIGURE 4 is a front elevation of the top unit of a second form ofvehicle drying apparatus, and

FIGURE 5 is a side elevation of the unit of FIGURE 4.

Both forms of apparatus illustrated, are designed to be mounted on alevel surface and both comprised a top unit, a near-side unit and anoff-side unit (only the top unit has been illustrated in the second formof apparatus). In each form of apparatus the near-side unit and theoff-side unit are disposed in spaced-apart relationship on oppositesides of a vehicle driveway so that the air stream from each side unitis directed across the driveway. The top unit is in each case disposedwith its air duct above the driveway so that the air stream is directeddownwardly onto the driveway.

Referring now to the embodiment of FIGURES 1 to 3, each unit comprises asupporting base 1 and an upstanding cylindrical casing 2 housing atwo-stage axialflow fan F, schematically indicated, and producing an airstream as indicated by the arrows S. The casing 2 is connected to apivotally mounted air duct 3 which tapers to a slit-shaped air outletnozzle 4-. The outlet nozzle 4 of each side unit extends at right anglesto the surface of the driveway and the outlet nozzle 4 of the top unitextends parallel to the surface of the driveway. The pivoting axis ofthe duct 3 of each side unit is directed vertically and the pivotingaxis of the duct 3 of the top unit is directed horizontally.

Each unit includes a silencer 18 which, in the case of each side unit ismounted .on top of the casing 2, and in the case of the top unit islocated in the base 1.

Each unit comprises a pair of sensing rollers 5 and 6 disposed inparallel spaced-apart relationship and connected together at each end byarcuate links 7. The sensing rollers 5 and 6 are mounted on each side ofthe respective nozzle 4 in the direction of travel of a vehicle alongthe driveway and each roller is, in the direction of air flowtherethrough, mounted forwardly of the nozzle.

Each unit also comprises a pivotally mounted pneumatically-operatedcylinder 8 which is coupled between the air duct 3 or 3 and a fixed partof the unit (i.e. the casing 2 in the case of each side unit and thebase 1 in the case of the top unit), and a pneumatic valve 9 forcontrolling the supply of compressed air to the cylinder 8. The assemblyof linked sensing rollers 5 and 6 is connected to the air duct 3 or 3 bya support arm 10 pivotally secured to the shaft of roller 5 and having avalve-actuating cam-surface 11 formed thereon. The sup port arm 10 ispivoted to the air duct 3 or 3' about a pivot pin 12. The valve 9 issecured to a valve mount 13, also pivoted about the pin 12 at one end,and rotatably linked to a controlling stay 14 at the other end. Theassembly of linked sensing rollers 5 and 6 is pivotally coupled at eachend to a supporting stay 15, each stay 15 being pivotally secured at 16to a fixed part of the unit.

The arrangement of linked sensing rollers 5 and 6, pivoted stays 14 and15, pivoted support arm 10 and pivoted valve mount 13 is such that ifundisturbed, the plane defined by the axes of the rollers 5 and 6 ofeach unit in one position of the duct 3 or 3' parallel to the planedefined by the rollers in any other position of the duct 3 or 3 and thatirrespective of the position of the duct 3 or 3', the valve 9 engagesthe same area of the cam surface 11 when the rollers are undisturbed.

If the assembly of rollers 5 and 6 is disturbed by the roller 6 beingpushed towards the nozzle 4, the cam surface 11 moves relative to thevalve 9 and causes'the cylinder 8 to pivot the duct 3 or 3 in an attemptto reduce the force displacing the roller 6. Movement of the duct 3 or3' will continue until force on the roller 6 is removed and the roller 6returns to its undisturbed position. The duct 3 or 3' of each unit isbiased so that if the respective sensing rollers are not displaced fromtheir undisturbed positions, the ducts move slowly across or towards thevehicle driveway. In the case of the top unit, this bias is obtained byproviding a counter-weight 17 which leaves a residual gravitationalturning moment acting on the duct 3, and in the case of each side unit,this bias is obtained by arranging the pneumatic system so that thecylinder 8 slowly urges the duct inwardly across the driveway when therollers and 6 are in their undisturbed positions.

The mode of operation of the apparatus is as follows. Let it be assumedthat the nozzle 4 of the top unit is in its lowest position and thenozzles of each side unit are in their positions of closest approach,and that a vehicle is driven slowly past the units along the driveway inthe direction of the arrows A. With the fans operating, the front of thevehicle moves towards the three nozzles which are defining avehicle-receiving space too small for the vehicle to pass through, andeventually a portion of the front of the vehicle strikes each of therollers 6, with the result that the rollers 6 are tilted from theirundisturbed positions. The nozzles retract from the vehicle until eachis disposed a short distance away from the adjacent surface of thevehicle. The biasing of the ducts has the effect of tending to urge themto reduce the vehicle-receiving space, a tendency which is prevented,during the passage of the vehicle past the nozzle of the respectiveduct, by the periodic contact of the sensing rollers 5 and 6 with theadjacent surface of the vehicle. As the vehicle moves through theapparatus the nozzle of each unit closely follows the contour of theadjacent surface of the vehicle so that highly efiicient drying isobtained. As the vehicle leaves the apparatus the ducts of the sideunits close together and the duct of the top unit drops in preparationfor the passage of the next. vehicle.

Referring now to the embodiment of FIGURES 4 and 5, the top unitillustrated comprises a supporting base 1 and an upstanding casing 2housing a two-stage axialflow fan F, schematically indicated andproducing an air stream as indicated by the arrows S. The casing 2 isconnected to a pivotally mounted air duct 3" with tapers to aslit-shaped air outlet nozzle 4. Mounted on the duct 3" and extendingforwardly of the nozzle 4 is a sensing means generally designated 19.The sensing means 19 is mounted on a bar 20 pivotally attached to theduct 3" adjacent to the nozzle 4 and the, bar 20 is coupled to thecasing 2 via a linkage 21. The linkage 21, ensures that as the ductpivots, the sensing means 19 maintains its orientation relative to ahorizontal plane.

The sensing means 19 embodies two distinct elements for sensing theproximity of the external surface of a vehicle, the normal sensingelement is formed by a photo-electric cell 22 and a light source 23which generates a beam that impinges on the cell 22. The second sensingelement which also embodies the cell 22, is formed by the roller 5movably mounted on the sensing means 19 and coupled to a shutter 24.

The pivoting shaft of the duct 3 is connected to an electromagneticbrake 25 and a counterweight 26. During operation of the unit, thereaction caused by air flowing out ofthe nozzle 4, exerts a thrust onthe duct 3 which urges the duct in a clockwise direction as shown inFIGURE 5. The duct 3 is counterweighted so that the gravitational forcedue to the weight of the duct is less than the lifting force due to thereaction to air flow, with the consequence that when the unit is beingoperated, the duct is subjected to a turning moment tending to cause thenozzle 4 to rise. Pivoting of the duct 3 is prevented by the brake 25.

The electromagnetic brake 25 can be adjusted to two limit positions, oneposition preventing pivoting of the duct 3" (and hereinafter referred toas the fully-on position) and a second position partially freeing thebrake and allowing slow pivoting of the duct (hereinafter referred to asthe partially-on position).

The photo-electric cell 22 is incorporated into the supply circuit 28for the electromagnetic brake 25, it being arranged that when the cell22 is illuminated by the source 23 the brake is held in the fully-onposition, but that when the light beam from the source 23 is obstructed,the brake 25 moves into the partially-on position. As the duct 3 pivotsand the nozzle 4 rises, the sensing means 19 rises too thus lifting thebeam to the cell 22 away from the object which caused the obstruction.It will be appreciated, therefore, that as a vehicle moves towards theunit the duct 3 will rise whenever the light beam is obstructed by apart of the vehicle and will continue to rise until the obstruction hasbeen cleared. By suitably adjusting the rate of rise of the duct,relative to the rate of advance of the vehicle, the unit can be set sothat the nozzle closely follows the contour. of the external surface ofthe vehicle.

In order toprotect against the possibility of the light beam not beingsufficiently obstructed by an object (e.g. by a slender object or atransparent object) the second sensing element is provided. If an objectmanages to pass through the light beam without causing the duct to lift,the object will eventually engage the shutter 24 into the light beam andthus initiate a lifting movement.

In practice, the unit would be employed in association tion with tripmechanisms (which may also be photoelectric) to start the fans on theapproach of a vehicle and to lower the duct after a vehicle has passed.This lowering of the duct may be effected merely by switching off thefans, deenergi-sing the brake 25 and allowing the duct to droopdownwardly under the influence of gravity. There are advantages however,in pulling the duct 3" down into its initial (and lowermost) positionwith a pneumatic cylinder 27.

The-specific descriptions given above are but two examples of apparatusin accordance with the invent-ion and many modifications could be madeto the apparatus describedaIn particular it can be pointed out thatalthough pneumatic control of the movements of the ducts is convenient,hydraulic control can be employed equally effectively, andin the case ofhydraulic control the more refined forms of hydraulic control valvesavailable make it possible to control more sensitively positions of theducts, so that for example, in the first form of apparatus, it ispossible for the respective assemblies of rollers to continuously engagethe surface ofv the vehicle during a drying operation. This greatersensitivity of control with an hydraulic system, arises because controlvalves can be employed which adjust the speed of movement of therelative ducts in response to the extent to which the rollers aredisplaced from their undisturbed positions.

What is claimedis:

1. Vehicle drying apparatus comprising support means, air duct meanshaving an outlet nozzle at one end and being movably mounted on saidsupport means, fan means communicating with the other end of said airduct means for blowing air through said outlet nozzle onto a vehiclepassing by said outlet nozzle, said air duct means being constructed andarranged on said support means so as to move, during operation of saidfan means, in a direction in which said outlet nozzle moves away fromthe vehicle, vehicle-sensing means mounted adjacent said nozzle, in adirection of air flow through the nozzle, forwardly thereof, and brakemeans connected to said air duct means to arrest movement of said airduct means in said direction, said sensing means cooperating with saidbrake means so as to render the latter ineffective when roller 5 to movethe 3 close proximity of said nozzle to a vehicle is sensed by saidsensing means.

2. Vehicle drying apparatus as defined in claim 1, wherein said air ductmeans is in the region of its other end pivotally mounted on saidsupport means.

3. Vehicle drying apparatus as defined in claim 2, wherein said supportmeans comprises a stationary casing and wherein said fan means ismounted in said casing.

4. Vehicle drying apparatus comprising at least one unit having acasing, fan means Within the casing, an air duct rmovably connected tothe casing for pivoting movement about an axis, an elongated nozzleforming the outlet of the duct at that end remote from its point ofattachment to the casing, the elongate direction of the nozzle beingparallel to the pivoting axis, brake means attached to the casing forimpeding movement of the duct about the pivoting axis, a counter weightfor balancing the weight of the duct to leave a residual turning momentabout the axis due to air flow through the nozzle, sensing means mountedon the duct, disposed in the direction of air flow through the nozzleforwardly of the, nozzle, said sensing means comprising at least oneroller movably mounted on the duct for movement towards the nozzle, froma rest position to a disturbed position, and control means for the brakemeans operatively connected to the sensing means for releasing the brakemeans in a disturbed position of said sensing means.

5. Drying apparatus as claimed in claim 4, in which said brake means isan electromagnetic brake and said sensing means embodies :aphotoelectric cell in a control circuit to said electromagnetic brake,and a light-source generating a light beam irradiating said cell, saiddisturbed position of the roller resulting in obstruction of the lightbeam.

6. Vehicle drying apparatus comprising at least one unit having acasing, fan means Within the casing, an air duct mova bly connected tothe casing for pivoting movement about an axis, an elongated nozzleforming the outlet of the duct at that end remote from its point ofattachment to the casing, the elongate direction of the nozzle beingparallel to the pivoting axis, means attached to the duct forcontrolling the movement of the latter about the pivoting axis, aphotoelectric cell and a light source for irradiating said cell mountedon opposite sides of the duct and aligned with an imaginary lineextending in the direction of air flow through the nozzle forwardly ofthe nozzle and parallel thereto, said photoelectric cell forming part ofan electrical control circuit for said means controlling the movement ofthe duct, whereby when said imaginary line is crossed by an opaqueobject said duct moves to restore full irradiation of said cell by saidlight sounce.

References Cited UNITED STATES PATENTS 2,321,983 6/1943 B-rackett.

2,904,894 9/1959 Hurst 34-87 X 2,925,801 2/1960 Bivens et a1.

3,224,108 12/1965 Flaming 34-87 FREDERICK L. MATTESON, JR., PrimaryExaminer. A. D. HERRMANN, Assistant Examiner.

1. VEHICLE DRYING APPARATUS COMPRISING SUPPORT MEANS, AIR DUCT MEANSHAVING AN OUTLET NOZZLE AT ONE END AND BEING MOVABLY MOUNTED ON SAIDSUPPORT MEANS, FAN MEANS COMMUNICATING WITH THE OTHER END OF SAID AIRDUCT MEANS FOR BLOWING AIR THROUGH SAID OUTLET NOZZLE ONTO A VEHICLEPASSING BY SAID OUTLET NOZZLE, SAID AIR DUCT MEANS BEING CONSTRUCTED ANDARRANGED ON SAID SUPPORT MEANS SO AS TO MOVE, DURING OPERATION OF SAIDFAN MEANS, IN A DIRECTION IN WHICH SAID OUTLET NOZZLE MOVES AWAY FROMTHE VEHICLE, VEHICLE SENSING MEANS MOUNTED ADJACENT SAID NOZZLE, IN ADIRECTION OF AIR FLOW THROUGH THE NOZZLE, FORWARDLY THEREOF, AND BRAKEMEANS CONNECTED TO SAID AIR